In this latest effort, the Chinese team reports that they obtained 213 fertilized eggs from a fertility clinic, which had been deemed unsuitable for in vitro therapy. The women who had donated the eggs all gave permission for the embryos to be used for genetic research, on condition that the embryos would not be allowed to mature into a human being. The team used the CRISPR technique to edit genes, adding a mutation that causes damage to an immune cell gene called CCR5—such cells that are damaged naturally have been found to lead to HIV resistance. Thus the point of the research was to learn more about the possibility of producing human babies that would be immune to HIV. The team reports that just 4 out of 26 of the embryos that were edited were modified successfully—some still contained genes that had not been modified, and others had resulted in unexpected gene mutations. All of the embryos were destroyed after three days. Due to the results, it is not clear what has been learned from the experiments, except that some groups, particularly in China, are willing to conduct such research despite international condemnation.